Re: git-svn failure when symlink added in svn

Eric Wong [off-list ref] writes:

I can't reproduce it on Linux with ext3.  I translated your recipe into
a test script in the patch below.  Anybody familiar with OSX and/or HFS
know if there's a workaround or fix for this?

Thanks for sending the test case.  It doesn't properly fail for me on
OSX, but if I run it with -v then I do see the error (so it is failing
on OSX and, as you found, not on Linux).

I added a silly print statement to see the symlink args:

diff --git a/entry.c b/entry.c
index d72f811..70f6402 100644
--- a/entry.c
+++ b/entry.c

@@ -129,6 +129,7 @@ static int write_entry(struct cache_entry *ce, char *path, struct checkout *stat
                                return error("git-checkout-index: unable to write file %s",
                                        path);
                } else {
+                        fprintf(stderr, "symlink: '%s' => '%s'\n", path, new);
                        wrote = symlink(new, path);
                        free(new);
                        if (wrote)

And so then on Linux with -v I get (after snipping most of the
output):

   * expecting success: 
           cd git &&
                   git svn rebase
                   cd ..
   
           A       bar.txt
   r2 = 31e734669e3fe4dbbd375e5a9f5af828a5b7ba92 (git-svn)
           D       foo.txt
   r3 = bd3b318730e8efc77235976abb18d04bc927bf9e (git-svn)
           A       foo.txt
   r4 = 2376eedcfec1de7cbe69b2bbad1c5de231a0ed0d (git-svn)
   First, rewinding head to replay your work on top of it...
   symlink: 'foo.txt' => 'bar.txt'
   HEAD is now at 2376eed... add foo as symlink
   Fast-forwarded master to refs/remotes/git-svn.
   *   ok 4: rebase in git-svn
   
   * passed all 4 test(s)

On my OSX laptop I get:

   * expecting success: 
           cd git &&
                   git svn rebase
                   cd ..
   
           A       bar.txt
   r2 = 4964f302b94ede0301b33faf5f4242c4bab3108b (git-svn)
           D       foo.txt
   r3 = 178a9ff3c7013d4ad8ec7defa93b91a1080c1e53 (git-svn)
           A       foo.txt
   r4 = 9f0bc38df8113fe1e11e47b708589d82bfa035a0 (git-svn)
   First, rewinding head to replay your work on top of it...
   symlink: 'foo.txt' => ''
   error: git-checkout-index: unable to create symlink foo.txt (Invalid argument)
   HEAD is now at 9f0bc38... add foo as symlink
   Fast-forwarded master to refs/remotes/git-svn.
   *   ok 4: rebase in git-svn
   
   * passed all 4 test(s)

If you're still with me, the curious part is what the symlink call is
trying to do.

  Linux:    symlink: 'foo.txt' => 'bar.txt'
    OSX:    symlink: 'foo.txt' => ''

So it looks like the problem is some sort of off-by-one that happens
well before the symlink call.  Perhaps this is enough for someone more
knowledgable than me to have a clue where to look next?

+ seth